This invention relates to a camera shutter, and more particularly to a shutter which can be used in photographic (i.e., still) cameras as well as in cinematographic cameras.
The prior art has proposed camera shutters having at least one diaphragm leaf which is displaced by a drive motor so as to vary the shutter aperture. However, these proposals are not entirely satisfactory, for a variety of reasons. The diaphragm leaf cannot be directly driven by the motor, so that a step-down transmission is required which, in the case of the prior-art proposals, is invariably rather complicated; this entails relatively high manufacturing costs. Also, the more complicated such a transmission, the bulkier it is which is a decided disadvantage in cameras, especially in view of the current trend to smaller and smaller cameras. In addition, the prior-art transmissions have relatively high friction losses which can be overcome only by providing a more powerful motor; this is undesirable not only from a cost point of view but also because it tends to more rapidly deplete the batteries which supply the motor with electrical energy.